Permutation switch

ABSTRACT

A plurality of tumblers are rotated by means made operable by selective movements of a combination dial to place conductive or dielectric peripheral regions of the tumblers in circuit making or breaking contact with spring contact fingers. The tumblers comprise annular outer portions surrounding inner portions which are independently rotatably mounted on a shaft. Releasable lock members normally connect the two tumbler portions together for conjoint rotation. A pin is insertable from the rear of the switch through openings in the outer tumbler portions to both move the lock member into release positions and lock such outer portions together. This permits use of the dial to change the azimuthal position of the peripheral segments relative to the dial indicia to change the combination of the switch. The spring fingers are portions of a circuit board which also includes conductors leading from the fingers to terminals. The circuit board is made flat and is then folded and installed into openings for same formed in a dielectric support member.

United States Patent Davidson 1 Sept. 12, 1972 PERMUTATION SWITCH [72]Inventor: William J. Davidson, Scio, Oreg.

[73] Assignee: Electronic Controls Corporation,

Scio, Oreg.

[22] Filed: Feb. 17, 1971 [21] Appl. No.: 116,172

Related U.S. Application Data [63] Continuation-impart of Ser. No.29,528, April Primary Examiner-Robert K. Schaefer AssistantExaminer-William J. Smith Attorney-Graybeal, Cole & Barnard [57]ABSTRACT A plurality of tumblers are rotated by means made operable byselective movements of a combination dial to place conductive ordielectric peripheral regions of the tumblers in circuit making orbreaking contact with spring contact fingers. The tumblers compriseannular outer portions surrounding inner portions which areindependently rotatably mounted on a shaft. Releasable lock membersnormally connect the two tumbler portions together for conjointrotation. A pin is insertable from the rear of the switch throughopenings in the outer tumbler portions to both move the lock member intorelease positions and lock such outer portions together. This permitsuse of the dial to change the azimuthal position of the peripheralsegments relative to the dial indicia to change the combination of theswitch.

The spring fingers are portions of a circuit board which also includesconductors leading from the fingers to terminals. The circuit board ismade flat and is then folded and installed into openings for same formedin a dielectric support member.

14 Claims, 15 Drawing Figures PATENTEDsEPmsn 3,691,328

sum 2 or 4 INVENTOR. W/ZZ/A/W J. DAV/D50 PERMUTATION SWITCHCROSS-REFERENCES TO RELATED APPLICATIONS This application is acontinuation-in-part of my copending application Serial No. 29,528,filed April 17, 1970, and entitled Permutation Switch.

BACKGROUND OF THE INVENTION 1. Field of the Invention This inventionrelates to improvements in permutation switches of the general typeshown and described in: U.S. Pat. No. 2,797,271, granted June 25, 1957to Arthur L. Augustine; U.S. Pat. No. 2,984,717, granted May 16, 1961 toRaymond W. Davidson and U.S. Pat. No. 3,192,331, granted June 29, 1965to Raymond W. Davidson.

2. Description of the Prior Art Each of the aforementioned U.S. Pat.Nos. 2,797,271; 2,984,717 and 3,192,331 shows a permutation switch ofthe general type to which the present inventi'on relates. In a switch ofthis type a plurality of disc-like tumblers are arranged for freeselective rotation about a support shaft mounted in a case. The tumblerperipheries have conductor and insulator regions. Contact brushes orfingers are mounted on the inside of a lateral wall of the case andproject radially inwardly into contact with the peripheries of thetumblers. A combination dial is secured to one end of the shaft and aradial arm is secured to the opposite end. This radial arm and somerotary motion transmitting abutments on the tumblers function uponselective movements of the dial to temporarily couple the tumblers tothe shaft, so that further shaft movement causes tumbler movement.

In the permutation switches disclosed by these three patentsmulti-position connections are provided between the shaft and theactuator arm so that the operating combination of the switch can bechanged by a simple change in the azimuthal position of the actuator armrelative to the shaft. Also, U.S. Pat. No. 3,192,331 discloses amulti-position connection between the operating dial and the shaft,permitting further changes in the operating combination. As can bereadily appreciated, in these prior art switches the number ofcombination changes achievable is a limited number, dependent upon thepossible number of different azimuthal position settings of the actuatorarm and/or operating dial relative to the shaft. Also, assembly anddisassembly of the internal switch parts is a problem. This is becausethe contact fingers are leaf springs and must be held out of engagementwith the tumblers during installation and removal of the contact fingersand their support from the switch housing. If not done properly, thecontact fingers can be distorted out of shape, broken, or both.

Permutation switch tumblers having inner and outer parts which aremovable relative to each other for the purpose of changing the switchcombination are disclosed by the following U.S. Pat: No. 389,703,granted Sept. 18, 1888 to Charles Hill; U.S. Pat. No. 1,381,409 grantedJune 14, 1921 to J. A. Freeze; U.S. Pat. No. 1,469,651 granted Oct. 2,1923 to L. F. Hymel; U.S. Pat. No. 1,670,448 granted May 22, 1928 toFrank Hanna; U.S. Pat. No. 1,725,086 granted Aug. 20, 1929 to EN.Larson; U.S. Pat. No. 1,744,707 granted Jan. 21, 1930 to S. de Castro EIznaga; U.S. Pat. No.

3,237,435 granted Mar. 1, 1966 to George D. Paul and U.S. Pat. No.3,254,519 granted June 7, 1966 to George D. Paul. However, none of thesepatents discloses a switch in which the inner and outer tumbler partsare unlocked by a pin which is inserted through an opening in the backof the switch and then axially through all of the outer tumblerportions, so that a new combination may be dialed.

SUMMARY OF THE INVENTION A principal object of the present invention isto provide multi-position connections between the conductive ordielectric region carrying portions of the tumblers and the dialcontrolled tumbler rotating elements, for the purpose of providing analmost infinite number of combination settings.

According to the invention, each tumbler comprises an inner portionwhich is freely rotatable. about the support shaft, and an annular outerportion which concentrically surrounds the inner portion. The outerportion carries the make or break regions of the tumblers. A releasablelock means normally connects the two tumbler portions together forconjoint rotation. When the lock means are released the inner tumblerportions are rotatable relative to the outer tumbler portions.

In the preferred embodiment of the present invention, the lock means arearranged so that they can all be simultaneously moved into their releasepositions by an elongated pin inserted from the rear of the switchthrough aligned openings in the outer portions of the tumbler. The pinserves to both release the lock means and to secure together the outerportions of the tumblers. In operation, the dial is turned in accordancewith the existing combination of the switch to place the conductive ordielectric regions of the tumblers in a circuit making or breakingposition relative to the contact brushes or fingers. The pin element isthen inserted through the tumbler outer portions for the purpose ofreleasing the lock means and also holding the outer tumbler portionstogetherand the conductive or dielectric segments thereof aligned. Next,the dial is manipulated for the purpose of changing the relativeazimuthal positions of the inner tumbler portions, and the tumblerrotation causing elements thereon, relative to the outer tumblerportions and the conductive or dielectric regions thereon. Thismanipulation also serves to change the relative azimuthal positions ofthe conductive or dielectric regions relative to the indicia on thedial. The pin is then removed, permitting automatic return of the lockmeans to their lock positions. This readies the switch for furtheroperation by use of the new combination.

Another principal feature of the present invention is the provision of anovel inner casing and electrical contact finger assembly constructionwhich facilitates manufacturing and assembly of the switches. Accordingto the invention, each switch is provided with a longitudinally splitinner casing of a dielectric material. Each casing part is adapted to beradially joined with the other part to form a cylindrical casing. Eachpart includes an axial recess formed in its outer surface for receivinga folded portion of a circuit board, and side windows in the recess foraccommodating contact finger portions of the circuit board. A generallyradial slot is provided in a radial end wall of each part to portshelves for the opposite ends of the contact fingers are provided at theregion of the windows and also laterally across the inner casing part.

The circuit board provides the contact fingers which ride on theperipheries of the tumblers and the conductors leading from such fingersto terminals at which wires are connected to the switch. The circuitboards are initially formed in a flat condition The conductive areas maybe formed by printing, depositing, or by otherwise providing conductivestrips or areas on a nonconductive base member or substrate. Then thecircuit board is folded into a particular configuration for insertioninto the recess, windows, slots and other regions formed for them in thecasing inner parts. The inner casing parts are moved radially intoengagement with the tumbler set. The spring contact fingers deflect andapply an inward force on the tumblers when the casing parts are inplace. The assemblage of the casing parts and the tumbler set is thenslid axially into an outer switch casing. At no time do the contactfingers have to be sprung radially'outwardly by a tool so that eitherthey or the tumbler set can be installed or which are exemplified by theembodiments hereinafter described.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is an axial sectional view of anembodiment of the invention, with some internal parts shown in sideelevation;

FIG. 2 is an exploded isometric view of the embodiment:

FIG. 3 is a cross-sectional view taken substantially along line 3-3 ofFIG. 1;

FIG. 4 is a rear elevational view taken from the aspect denoted by line4-4 in FIG. 1;

FIG. 5 is an exploded isometric view of one of the tumblers, lookingtowards the side of the tumbler on which the locking member is located;

FIG. 6 is an assembled isometric view of the tumbler taken fromsubstantially the SAME aspect as FIG. 5;

FIG. 7 is an assembled isometric view of the tumbler taken from anaspect looking towards the opposite side of the tumbler;

FIG. 8 is a side elevational view of the tumbler, taken from an aspectlooking towards the same side of the tumbler that is the front side inFIG. 7;

FIG. 9 is an axial sectional view taken through the tumblersubstantially along line 99 of FIG. 8;

FIG. 10 is a side elevational view of the tumbler looking towards theside of the tumbler on which the locking member is situated;

FIG. 11 is an axial sectional view taken substantially along line 1ll1of FIG. 10;

FIG. 12 is a top plan view of an electrical contact finger-lead wirecircuit board;

FIG. ,13 is an isometric view of the circuit board showing it shaped foruse;

FIG. 14 is a fragmentary top plan view of a modified circuit board,usable in a normally open switch; and

FIG. 15 is a fragmentary top plan view of still another modified form ofcircuit board, formed to include a third conductor.

DESCRIPTION OF THE PREFERRED EMBODIMENT The present invention relates toboth normally open and normally closed switches. By way of typical andtherefore nonlimitive example, the invention is illustrated and will nowbe described in connection with a normally open switch.

Referring to FIG. 1, the switch 10 is shown to comprise a casing havinga cylindrical side wall 12, an integral front wall 14 and a removablerear cover plate 16.

A tumbler-supporting and operating shaft 18 is journaled, such as by ajournal 20, within anopening provided in the front wall 14. Shaft 18 isshown to have a non-circular (e.g. square) cross-sectional portion 22 atits forward end which snugly fits within a socket of similar shapeformed in a concealed control knob 24, and secured by a laterallyextending set screw 26. A conical entrance way 28 is formed in theforward portion of control knob 24. The side walls of entrance way 28slope radially inwardly towards a noncircular socket 30 for receiving asimilarly shaped inner end portion 32 of a combination dial 34, Theswitch 10 and the control knob 24 may be secured inside of a cabinet orbehind a wall or barrier 35 (FIG. 2), with access to it consisting onlyof a relatively small opening in the wall portion of the cabinet, or inthe barrier 35, which opening is coaxially aligned with the socket 30,for receiving the inner end portion 32 of the control dial 34.

As shown best by FIGS. 1 and 5-11, each tumbler T is in the form of atwo part circular disc or wheel. The inner part 36 has an axial opening38 therein sized for receiving a tubular bushing 40 which surrounds theshaft 18. The annular outer tumbler portion 42 includes a central axialopening 44 for receiving an axial extension 46 of the inner tumblerportion 36. Lock mechanisms, hereinafter to be described in detail,nor.- mally connect the two tumbler portions together for conjointrotation.

A radial actuator arm 44 (FIG. 1) is secured in a fixed position to therear end portion of the shaft 18. This arm 48 includes a noncircularopening at its mounted end in which is received a complementary shapedrear end portion of the shaft A a cotter pin 50 may extend through therear end portion of shaft 18 for the purpose of holding the arm 48 andthe tumblers T on the shaft surrounding sleeve 40. Arm 48 also includesa forwardly directed axial pin or abutment 51 which rides in a circularchannel 54 formed in the rear side of the inner tumbler portion 36.

An axially extending driving pin 52 (FIG. 7, for example) extendsforwardly from each tumbler inner portion 36. A radially extendingdriving abutment 56 (FIG 10, for example) is provided on the rear sideof each inner tumbler portion 36. The driving pin 52 of each tumbler Ttravels a collision path with the abutment 56 of the tumbler immediatelyforwardly of it. The driving web 56 of the rear tumbler T is positionedto be in the rotational path of the forwardly projecting pin 51 on arm48.

The periphery of each tumbler T is provided with adjoining V notches,some of which are designated 58,

defining between them transverse ridges or lands of triangular section.Each outer tumbler portion 42 is made from plastic or some otherdielectric material and a region of its periphery is recessed at 60(FIG. 5, for example) to receive a segment 62 of a conductive material.

As best shown by FIG. 2, a longitudinally split inner casing or housing,composed of complementary parts 64, 66 is received within the casing 12,14. These members 64, 66 are made from a dielectric material (egplastic) and serve to retain and properly position a pair of foldedcircuit board members 68, 70.

Reference is now made to FIGS. 12 and 13, depicting a circuit board 68.In FIG. 12 the board 68 is shown in its flat condition. It is shown toinclude a base member 72 of plastic, plasticized paper, etc. which isdielectric in nature. Conductive lead lines or paths 74, 76 are printed,deposited, or otherwise emplaced on the member 62. Also, an insulativelayer or laminate may be placed over the conductive paths 74, 76 toprovide an insulative cover therefor. One end of each conductive path74, 76 is connected to a flat, apertured terminal member 78, 80. Theopposite ends of the conductive paths 74, 76 connect to initially flat,outside located conductor members or fingers 82, 84.

The flat circuit boards 68, 70 are suitably folded and creased into theconfiguration shown by FIG. 13, for example. A portion 86 of each board68, at the base of the contact fingers 82, 84, is folded as pictured andis placed within an axially elongated, generally radial recess 88 formedin the housing member 64, 66. The contact fingers project chordwise ofthe housing member 64, 66, through windows provided for them in the sidewall of recess 88. Some of these windows are designated 90. A straightflat portion 92 of the circuit board 68, 70 is located within a slot 94formed in the end wall of the recess 88. A folded terminal carryingportion 96 of the circuit board 68, 70 is disposed rearwardly of thecover member 16, with the terminal end portions 78, 80 fitting withinrecesses formed therefor and are secured to the member 16 by means ofclamp screws 98, 100. v

The just described construction of the contact fingers 82, 84 and thelead conductors 74, 76 therefor can be mass produced economically andthey, together with the split construction of the inner housing 64, 66provide for an easy assembly of the internal working components of theswitch 10. The folded circuit boards 68, 70 are fitted onto the innerhousing parts 64, 66. As shown by FIG. 3, the free ends of the contactfingers 82, 84 rest on a shelf 102 which is substantially in coplanarparallelism with the similar shelf 104 at the base of the windows 90.The straight flat portions 92 of the circuit board member 68, 70 arepositioned within additional slots 108 in rear cover member 16 which arealignable with the slots 94. After the folded circuit boards 68, 70 areproperly assembled the inner housing parts 64, 66 are brought radiallytogether on opposite sides of the tumbler set 106 (FIG. 2). The tumblerset comprises the tumblers T and the sleeve 40. Next, the assemblage ofthe inner housing parts 64, 66, the folded circuit board 68, 70, thetumbler set 106 and cover 16 is slid endwise relatively into the outercasing 12, 14. Screw fasteners 110 are inserted through openings 112provided in the rear cover 16 and are threaded into interiorly tappedsockets formed in inner boss portions 114 which are integral with theside wall 12 of the casing 12, 14. The fasteners 110 secure the covermember to the casing 12, 14 and indirectly hold the assembled internalcomponents of the switch in proper position within the casing l2, 14.

Each set of contact fingers 82, 84 (i.e. each folded circuit board 68,forms with the set of tumblers T an independent switch. A simplevariation which would further increase the number of circuits of whichthe switch 10 may be a part would be to provide a separate lead-in wire(FIG. 15) for the rearmost paired contact fingers 82, 84. Then when theconductive segments 62 of the third and fourth tumblers T are broughtinto contact with the rearmost paired contact fingers 82, 84 a thirdcircuit will be formed between conductor 74 and the third conductor 75.The terminal 79 for the third conductor could be located betweenterminal 78, 80. In FIG. 4, the rear cover 16 is shown to include aclamp screw 116 and a socket for the third terminal associated with eachcircuit board 68, 70.

As shown by FIG. 1, two adjacent contact fingers 82, 84'ride on theserrated or grooved periphery of each tumbler T. As will be apparent,when the conductive segments 62 are aligned and are in contact with thefingers 82, 84, a series circuit is completed from one conductor 74through such fingers 82, 84 and the segment 62 to the other conductor76.

In a normally open switch the dielectric and conductive regions of thetumbler peripheries are reversed and the contact finger end of conductor74 includes a separate branch leading down to each contact finger 82,the contact finger end of conductor 76 includes a branch leading down toeach contact finger 84 (FIG. 14). A layer or ply of an insulativematerial is sandwiched between the two sets of branches. A seriescircuit is established from each finger 82 through its tumbler T to thecontact finger 84 in contact'with the same tumbler T. This occurswhenever a pair of associated contact fingers 82, 84 are in contact withthe conductive region of their tumbler T. The circuit of which theconductors 74, 76 are a part stays closed until all fingers 82, 84 arein contact with a dielectric region of a tumbler T.

The contact fingers 82, 84 in the illustrated embodiment, and thecontact fingers in the non-illustrated normally closed switchembodiment, are spring members and contain sufficient spring energy tonormally urge their central portions relatively tightly against theperiphery of the tumblers T. Preferably, the central portions of thecontact fingers 82, 84 are inwardly bent so as to form a projectionwhich closely fits with the V groov'es or valleys 58 (FIG. 3).

From the foregoing, it will be readily apparent that an electricalcircuit through the contact finger elements will remain open as long asany two of the contact fingers riding a tumbler T are in contact with adielectric portion of such tumbler T. In the normally open switch theelectrical circuit through the conductors 74, 76 will remain closed aslong as a single pair of the fingers 82, 84 are in contact with theconductive region of the tumbler T with which they are in contact. Themaking or breaking of the electrical circuit in either the normally openswitch or the normally closed switch can only be accomplished byrotating the tumblers T relative to each other about their supportingshaft means 18, 40, by means of the dialing knob 34, and then only by anauthorized person who has knowledge of the number of turns to the rightor left thereof to bring the various conductive or dielectric minorregions of the tumbler peripheries into contact with the contactfingers.

Initially, the knob 34, and hence shaft 18 and actuator arm 48, will berotated several revolutions, so as to bring the driving pins 51, 52,beginning with the arm 48, into engagement with the driving webs orabutments 56 of the adjacent tumblers T so that the successive tumblersT will in turn be picked up" and be rotated along with the arm 48. Thefirst stop at the indicator mark 120 (FIG. 2) will result in theconductive segment 62 of the front tumbler T being brought intoengagement with its respective contact fingers 82, 84, thus initiallyestablishing a current path through these two contact fingers and theforward conductive segment 62 alone.

With the front or first tumbler T now held against rotation (by thecontoured center region of the contact fingers 82, 84 engagement withthe V notches 58 in the conductive segment 62), the knob 34 is rotatedin the opposite direction. This causes the driving pin 51 on theactuator arm 48 to first disengage itself from one side of the drivingweb 56 of the rear tumbler, and to then rotate around into engagementwith the other side of said web 56, causing driving pin 52 of the rearor fourth tumbler T to pick up the web 56 of the third tumbler Timmediately forwardly thereof, to rotate the same in said oppositedirection. Pin 52 of the third tumbler T will pick up the web 56 of thesecond tumbler T, to rotate the same until its conductive segment 62 isengaged by the tips of its respective contact fingers 82, 84, and heldagainst further rotation thereby. With the first and second tumblers nowin the positions just mentioned, the circuit path has been extended toalso include the conductive region 62 of the second tumbler T and thetwo contact fingers 82, 84 in contact therewith. Additional rotation ofthe dial 34 and the actuator arm 48 in the original direction ofrotation will similarly impart rotation to the third tumbler T toposition its conductive segment 62 and the associated contact fingers82, 84 in a contact making position. Further rotation of dial 34 andactuator arm 48 in the reverse direction will finally position theconductive segment 62 of the rear tumbler T into circuit makingengagement with its two contact fingers 82, 84, thus completely theseries circuit through the contact fingers 82, 84 and the conductivesegment 62.

All of the dialing operations described, to be effective, must be donein accordance with the numerical combinations assigned to the switch inits entirety. Ac-

cording to the present invention the tumblers T are constructed so thatthey can be used to quickly and conveniently vary the relative azimuthalpositions of the pins and webs 52, 56 relative to the dial indicia toestablish almost an indefinite number of different combinations. Apreferred embodiment of the tumbler construction making the large numberof combination changes possible will now be described.

As best shown by FIGS. 9 and 11, the rear side of each outer tumblerportion 42 is recessed to receive a greater portion of the inner tumblerportion 36. The forward side of each outer tumbler portion 42 isrecessed at 120, immediately bordering the central opening 42, to form aone sided annular groove or rabbet that is slightly larger in diameterthan the central opening 44. The axial extension 46 of the inner tumblerportion 36 includes a radial flange or annulet 122 which is fittableinto the rabbet 120. The forward portion of the annulet 122 is beveledso that the inner tumbler portion 36 can be snapped fitted into theouter tumbler portion 42.

When the two tumbler portions 36, 42 assemble, and the annulet 122 isreceived in the rabbet (FIG. 9) the fit between the two tumbler portions36, 42 is a relatively loose one, so that the two portions 36, 42 can berather easily rotated, one relative to the other.

The lock means provided for normally connecting the inner and outertumbler portions 36, 42 together for conjoint rotation includes aradially movable lock member 124. Asbest shown by FIGS. 5 and 11, theouter tumbler portion 42 is formed to include a radial slideway 126 inwhich the lock member 124 is received. The slideway, 126 is defined inpart by a pair of wings 128, 130 which serve to retain the member 124 inthe slideway 126 in the axial direction. The fit between the lock member124 and the slideway 126 is loose enough to permit the member 124 tomove easily in the radial direction.

The inwardly directed end portion of member 124 is serrated or otherwisepatterned and the peripheral surface of the inner tumbler portion 36 iscomplementarily patterned at 134.

A circumferential groove 136 is formed in the member 42 radiallyoutwardly from the slideway 126. This groove 136 has a continuous outerradial boundary and includes inner radial restraining or boundary means138, 140 only at its ends. The intermediate portion of the spring seat136 is unrestrained or bounded in the radially inward direction. Anormally inwardly biased leaf spring 142 is fitted within the springseat 136. It includes an intermediate portion which rests on the lockmember 124 and serves to bias it radially inwardly, causing itsserrations 132 to mate with the serrations 134 on the inner tumbler part136.

A release pin receiving opening 144 is provided axially through theradial wall portion 146 of each tumbler outer portion 42 in a regionwhich is normally at least partially covered by a midportion of the lockmember 124. The angle X (FIG. 8) between the center of opening 144 andthe center of the conductive segment 62 is the same for each tumbler T.Thus, when the conductive segment 62 (or the dielectric segments in thenormally closed form of switch) are aligned with each other, theopenings 144 are also axially aligned with each other and with anopening 148 in the rear cover (FIG. 2).

An axial opening 150 is provided through each lock member 124. Eachopening 150 is surrounded by a camming surface 152. The leaf spring 142normally urges the member 124 into a position in which its opening 150is positioned slightly radially inwardly of the corresponding opening144, and the radially outer portion of the cam surface 152 is generallyaligned with the openings 144.

According to the present invention, the combination of a given switch 10is simply and quickly changed by a person dialing the existingcombination to place the segment 62 in line and the openings 144 inalignment with each other and with the rear cover opening 148. Then anelongated pin 154 is inserted successively first through the opening 148and then the openings 144 in the respective outer tumbler portions 42.Wall means 149 may be provided to make opening 148 be an elongated guidepassageway for the pin 154.

Since entrance into the openings 144 is partially blocked by the lockmembers 124, the pin 154 must first move the lock levers 124 out of theway. The sloping cam surface 152 serves to facilitate this movement. Theforce of the pin 154 on the incline set cam surface 152 causes anoutward sliding movement of the lock member 124 within its slideway 126against the resistance of the leaf spring 142. When pin 154 is situatedwithin the openings 144 it serves to hold the patterned end portions 132of the lock members 124 radially outwardly from a position of lockingengagement with the patterned peripheries 134 of the inner tumblerportions 136. It also serves to lock together the outer tumbler portions42 and hold them in a constant position with respect to the contactfingers 82, 84. The operator then manipulates the dial 34 to reset thecombination. Rotation of the dial 34 and the shaft 18 causes rotationalmovement of the tumbler inner portions 36 via the arm 44, its pin 51,the pins 52 and the abutments 56. Once a new combination is establishedthe pin 154 is removed, resulting in a return of the lock members 124 tolocking positions. Thereafter the switch is operable by the newcombination.

According to the invention, a second spring seat 156 is locateddiametrically across the tumbler outer portion 42 from spring seat 136.It is .of similar construction, having means at its two ends for holdinga second leaf spring 158. This second leaf spring 158 is biased radiallyinwardly and rests on the pattern periphery 134 of the tumbler innerportion 36. Its function is to retard relative rotation between the twotumbler parts 36, 42, so that rotation will not occur unless it ispositively caused by a rotation of the inner tumbler portion 36 relativeto the outer tumbler portion 42. [n this respect it has the samerotational retarding effect as the contact fingers 82, 84 on thetumblers T in their entireties.

Obviously, many modifications and variations of the present inventionare possible in light of the above teachings. it is therefore to beunderstood that within the scope of the appended claims, the inventioncan be practiced otherwise than as specifically described.

What is claimed is:

l. A permutation switch tumbler comprising an inner portion which in userotates about a central support; an annular outer portion surroundingsaid inner portion, said outer portion having conductive and dielectricregions; and a radially movable releasable lock member carried by one ofsaid portions, said lock member being movable radially between a lockposition wherein it makes locking engagement with the other portion andthe two portions are locked together for conjoint rotation, and arelease position wherein it is free of engagement with said otherportion and the two tumbler portions are rotatable relative to eachother, said lock member including an oblique side located cam surfaceoriented such that a generally axial inward force against said surfacewill cause a radial sliding movement of the locking lever from its lockposition into its release position.

2. A permutation switchtumbler according to claim 1, wherein said innerportion has a patterned periphery, said lock member is carried by saidouter portion and has a patterned end portion directed towards saidperiphery, and said tumbler further includes spring means normallyurging said releasable lock member towards the inner portion and itspatterned free end portion against the patterned periphery of said innerportion.

3. A permutation switch tumbler according to claim 2, further includingsecond spring means anchored on said outer portion and exerting a dragforce on said inner portion when the two portions are not lockedtogether.

4. A permutation switch tumbler according to claim 1 wherein said outerportion comprises a radially directed slideway for receiving the lockmember, and a circumferentially extending leaf spring retaining recesspositioned radially outwardly of said slideway, wherein said lock memberis slidably received in said slideway, and wherein a springis containedwithin said spring recess, said spring serving to normally urge the lockmember radially inwardly toward the inner portion of the tumbler.

5. A permutation switch tumbler according to claim 4, wherein saidspring means is a leaf spring and said spring recess includes meansholding the end portions of said leaf spring, with an intermediateportion of said spring being bowed and in force applying contact withsaid lock member.

6. in a permutation switch of a type comprising a plurality of coaxial,independently rotatable, generally cylindrical tumblers, each of whichhas conductive and dielectric peripheral regions, conductor elementsresting on the periphery of each tumbler, a tumbler control member, andmeans associated with said tumblers and operable upon selective rotationof said tumbler control member for rotating said tumblers into positionswherein the conductive segments are in circuit-making contact with theconductor elements or the dielectric regions are in circuit-breakingcontact with the conductor elements, the improvement comprising: saidconductor elements comprising a plurality of spring fingers, and saidswitch including a circuit board to which end portions of said fingersare secured, electric conductor strips on said circuit board extendingfrom at least some of said fingers, each to a terminal, said tumblersbeing at least partially surrounded by a dielectric support memberformed to engage portions of said circuit board and hold said fingers inposition to contact said tumblers.

7. The permutation switch improvement of claim 6, wherein saiddielectric support member includes a recess for receiving a portion ofthe circuit board which is situated adjacent where the spring fingersconnect to the circuit board.

8. The permutation switch improvement of claim 6, wherein said supportmember includes means for supporting the opposite ends of the springfingers, said spring fingers being unrestrained between their ends andeach including an intermediate portion which is in contact with theperiphery of one of the tumblers.

9. The permutation switch improvement of claim 6, further including awall portion formed to include terminal stations, with said circuitboard including a portion extending to said terminal stations andserving to place the said terminals at said terminal stations.

10. The permutation switch improvement of claim 9, wherein said wallportion is a radial wall spaced rearwardly of said tumblers, said radialwall includes a slot for receiving a portion of the circuit board, and aterminal end portion of the circuit board is on the opposite side ofsaid wall from said tumblers and is folded back against said radialwall.

11. The permutation switch improvement of claim 6, wherein saiddielectric support member is in part at least a segment of a cylinder,said member includes an axially extending recess formed in an outerportion thereof which is sized to receive a portion of the circuit boardwhich is situated immediately inwardly of where the spring fingersconnect to the circuit board.

12. The permutation switch improvement of claim 1 1, wherein saidcircuit board is folded back on itself at least once in the regionthereof which is received in said recess.

13. The permutation switch improvement of claim 11, wherein said supportmember includes means for supporting the opposite ends of the springfingers, said spring fingers being unrestrained between their ends andeach including an intermediate portion which is in contact with theperiphery of one of the tumblers.

14. The permutation switch improvement of claim 12, wherein said supportmember includes means for supporting the opposite ends of the springfingers, said spring fingers being unrestrained between their ends andeach including an intermediate portion which is in contact with theperiphery of one of the tumblers.

1. A permutation switch tumbler comprising an inner portion which in userotates about a central support; an annular outer portion surroundingsaid inner portion, said outer portion having conductive and dielectricregions; and a radially movable releasable lock member carried by one ofsaid portions, said lock member being movable radially between a lockposition wherein it makes locking engagement with the other portion andthe two portions are locked together for conjoint rotation, and arelease position wherein it is free of engagement with said otherportion and the two tumbler portions are rotatable relative to eachother, said lock member including an oblique side located cam surfaceoriented such that a generally axial inward force against said surfacewill cause a radial sliding movement of the locking lever from its lockposition into its release position.
 2. A permutation switch tumbleraccording to claim 1, wherein said inner portion has a patterNedperiphery, said lock member is carried by said outer portion and has apatterned end portion directed towards said periphery, and said tumblerfurther includes spring means normally urging said releasable lockmember towards the inner portion and its patterned free end portionagainst the patterned periphery of said inner portion.
 3. A permutationswitch tumbler according to claim 2, further including second springmeans anchored on said outer portion and exerting a drag force on saidinner portion when the two portions are not locked together.
 4. Apermutation switch tumbler according to claim 1 wherein said outerportion comprises a radially directed slideway for receiving the lockmember, and a circumferentially extending leaf spring retaining recesspositioned radially outwardly of said slideway, wherein said lock memberis slidably received in said slideway, and wherein a spring is containedwithin said spring recess, said spring serving to normally urge the lockmember radially inwardly toward the inner portion of the tumbler.
 5. Apermutation switch tumbler according to claim 4, wherein said springmeans is a leaf spring and said spring recess includes means holding theend portions of said leaf spring, with an intermediate portion of saidspring being bowed and in force applying contact with said lock member.6. In a permutation switch of a type comprising a plurality of coaxial,independently rotatable, generally cylindrical tumblers, each of whichhas conductive and dielectric peripheral regions, conductor elementsresting on the periphery of each tumbler, a tumbler control member, andmeans associated with said tumblers and operable upon selective rotationof said tumbler control member for rotating said tumblers into positionswherein the conductive segments are in circuit-making contact with theconductor elements or the dielectric regions are in circuit-breakingcontact with the conductor elements, the improvement comprising: saidconductor elements comprising a plurality of spring fingers, and saidswitch including a circuit board to which end portions of said fingersare secured, electric conductor strips on said circuit board extendingfrom at least some of said fingers, each to a terminal, said tumblersbeing at least partially surrounded by a dielectric support memberformed to engage portions of said circuit board and hold said fingers inposition to contact said tumblers.
 7. The permutation switch improvementof claim 6, wherein said dielectric support member includes a recess forreceiving a portion of the circuit board which is situated adjacentwhere the spring fingers connect to the circuit board.
 8. Thepermutation switch improvement of claim 6, wherein said support memberincludes means for supporting the opposite ends of the spring fingers,said spring fingers being unrestrained between their ends and eachincluding an intermediate portion which is in contact with the peripheryof one of the tumblers.
 9. The permutation switch improvement of claim6, further including a wall portion formed to include terminal stations,with said circuit board including a portion extending to said terminalstations and serving to place the said terminals at said terminalstations.
 10. The permutation switch improvement of claim 9, whereinsaid wall portion is a radial wall spaced rearwardly of said tumblers,said radial wall includes a slot for receiving a portion of the circuitboard, and a terminal end portion of the circuit board is on theopposite side of said wall from said tumblers and is folded back againstsaid radial wall.
 11. The permutation switch improvement of claim 6,wherein said dielectric support member is in part at least a segment ofa cylinder, said member includes an axially extending recess formed inan outer portion thereof which is sized to receive a portion of thecircuit board which is situated immediately inwardly of where the springfingers connect to the circuit board.
 12. The permutation switchimproveMent of claim 11, wherein said circuit board is folded back onitself at least once in the region thereof which is received in saidrecess.
 13. The permutation switch improvement of claim 11, wherein saidsupport member includes means for supporting the opposite ends of thespring fingers, said spring fingers being unrestrained between theirends and each including an intermediate portion which is in contact withthe periphery of one of the tumblers.
 14. The permutation switchimprovement of claim 12, wherein said support member includes means forsupporting the opposite ends of the spring fingers, said spring fingersbeing unrestrained between their ends and each including an intermediateportion which is in contact with the periphery of one of the tumblers.